Remove task.h and finish base::Bind() migration.

chrome/browser/ui/webui/chromeos/imageburner/webui_handler.h

Index: chrome/browser/ui/webui/chromeos/imageburner/webui_handler.h
diff --git a/chrome/browser/ui/webui/chromeos/imageburner/webui_handler.h b/chrome/browser/ui/webui/chromeos/imageburner/webui_handler.h
index 972ed9d533cb7b227085756031761cf7b5559f65..dc8d061a9b6197529378134992281e75f84bd820 100644
--- a/chrome/browser/ui/webui/chromeos/imageburner/webui_handler.h
+++ b/chrome/browser/ui/webui/chromeos/imageburner/webui_handler.h
@@ -9,6 +9,7 @@
 #include <string>
 
 #include "base/file_path.h"
+#include "base/memory/weak_ptr.h"
 #include "base/string16.h"
 #include "base/values.h"
 #include "chrome/browser/chromeos/cros/burn_library.h"
@@ -59,8 +60,6 @@ class WebUIHandlerTaskProxy
   // we need to post back to the UI thread for destruction.
   void DeleteOnUIThread();
 
-  void DoNothing() {}
-
  private:
   base::WeakPtr<Delegate> delegate_;